diff options
| author |   Vincent Whitchurch <vincent.whitchurch@axis.com> | 2018-09-03 16:23:36 +0200 |
|---|---|---|
| committer |   David S. Miller <davem@davemloft.net> | 2018-09-05 22:09:37 -0700 |
| commit | fa788d986a3aac5069378ed04697bd06f83d3488 (patch) | |
| tree | e335abac12b88e196f4c7c9e1012a66e93f53830 /net/core/dev.c | |
| parent | net: lan743x_ptp: make function lan743x_ptp_set_sync_ts_insert() static (diff) | |
| download | linux-dev-fa788d986a3aac5069378ed04697bd06f83d3488.tar.xz linux-dev-fa788d986a3aac5069378ed04697bd06f83d3488.zip | |
packet: add sockopt to ignore outgoing packets
Currently, the only way to ignore outgoing packets on a packet socket is
via the BPF filter. With MSG_ZEROCOPY, packets that are looped into
AF_PACKET are copied in dev_queue_xmit_nit(), and this copy happens even
if the filter run from packet_rcv() would reject them. So the presence
of a packet socket on the interface takes away the benefits of
MSG_ZEROCOPY, even if the packet socket is not interested in outgoing
packets. (Even when MSG_ZEROCOPY is not used, the skb is unnecessarily
cloned, but the cost for that is much lower.)
Add a socket option to allow AF_PACKET sockets to ignore outgoing
packets to solve this. Note that the *BSDs already have something
similar: BIOCSSEESENT/BIOCSDIRECTION and BIOCSDIRFILT.
The first intended user is lldpd.
Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/core/dev.c')
| -rw-r--r-- | net/core/dev.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/net/core/dev.c b/net/core/dev.c index 82114e1111e6..ca78dc5a79a3 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -1969,6 +1969,9 @@ void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev) rcu_read_lock(); again: list_for_each_entry_rcu(ptype, ptype_list, list) { + if (ptype->ignore_outgoing) + continue; + /* Never send packets back to the socket * they originated from - MvS (miquels@drinkel.ow.org) */ |